added get_last_error_message; still working on its unit test

fortran/lammps.f90

@@ -101,6 +101,7 @@ MODULE LIBLAMMPS
       PROCEDURE :: version                => lmp_version
       PROCEDURE :: is_running             => lmp_is_running
       PROCEDURE :: has_error              => lmp_has_error
+      PROCEDURE :: get_last_error_message => lmp_get_last_error_message
   END TYPE lammps
 
   INTERFACE lammps
@@ -416,12 +417,18 @@ MODULE LIBLAMMPS
     !SUBROUTINE lammps_force_timeout
 
     INTEGER (C_int) FUNCTION lammps_has_error (handle) BIND(C)
-      IMPORT :: C_ptr, C_int
+      IMPORT :: c_ptr, c_int
       IMPLICIT NONE
-      TYPE(C_ptr), VALUE :: handle
+      TYPE(c_ptr), VALUE :: handle
     END FUNCTION lammps_has_error
 
-    !INTEGER (c_int) FUNCTION lammps_get_last_error_message
+    INTEGER (c_int) FUNCTION lammps_get_last_error_message &
+        (handle, buffer, buf_size) BIND(C)
+      IMPORT :: c_ptr, c_int, c_char
+      IMPLICIT NONE
+      TYPE(c_ptr), VALUE :: handle, buffer
+      INTEGER(c_int), VALUE :: buf_size
+    END FUNCTION lammps_get_last_error_message
 
   END INTERFACE
 
@@ -852,12 +859,40 @@ CONTAINS
   ! equivalent function to lammps_has_error
   LOGICAL FUNCTION lmp_has_error(self)
     CLASS(lammps), INTENT(IN) :: self
-    INTEGER(C_int) :: has_error
+    INTEGER(c_int) :: has_error
 
     has_error = lammps_has_error(self%handle)
-    lmp_has_error = (has_error /= 0_C_int)
+    lmp_has_error = (has_error /= 0_c_int)
   END FUNCTION lmp_has_error
 
+  ! equivalent function to lammps_get_last_error_message
+  SUBROUTINE lmp_get_last_error_message(self, buffer, status)
+    CLASS(lammps), INTENT(IN) :: self
+    CHARACTER(LEN=*), INTENT(OUT) :: buffer
+    INTEGER, INTENT(OUT), OPTIONAL :: status
+    INTEGER(c_int) :: length, Cstatus, i
+    TYPE(c_ptr) :: Cbuffer
+
+    buffer = ''
+    IF ( lmp_has_error(self) ) THEN
+      length = LEN(buffer)
+      Cbuffer = f2cstring(buffer)
+      Cstatus = lammps_get_last_error_message(self%handle, Cbuffer, length)
+      length = MIN(LEN(buffer), c_strlen(Cbuffer))
+      FORALL ( i=1:length )
+        buffer(i:i) = Cbuffer(i)
+      END FORALL
+      IF ( PRESENT(status) ) THEN
+        status = Cstatus
+      END IF
+    ELSE
+      buffer = ''
+      IF ( PRESENT(status) ) THEN
+        status = 0
+      END IF
+    END IF
+  END SUBROUTINE lmp_get_last_error_message
+
   ! equivalent function to lammps_is_running
   LOGICAL FUNCTION lmp_is_running(self)
     CLASS(lammps), INTENT(IN) :: self

unittest/fortran/wrap_properties.cpp

@@ -111,5 +111,6 @@ TEST_F(LAMMPS_properties, extract_setting)
 
 TEST_F(LAMMPS_properties, has_error)
 {
-   EXPECT_EQ(f_lammps_has_error(), 0);
+   EXPECT_EQ(f_lammps_has_error(), lammps_has_error(lmp));
+   // TODO: How to test the error message itself?
 };